net: freescale: ucc_geth: Move the serdes configuration around

net: freescale: ucc_geth: Move the serdes configuration around

The uec_configure_serdes() function deals with serialized linkmodes
settings. It's used during the link bringup sequence. It is planned to
be used during the phylink conversion for mac configuration, but it
needs to me moved around in the process. To make the phylink port
clearer, this commit moves the function without any feature change.

Signed-off-by: Maxime Chevallier <maxime.chevallier@bootlin.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>